Proximity detection is useful in a variety of contexts including inventory management, building security, and environmental mapping and navigation. One proximity detection technology known as RFID (radio-frequency identification) uses an RFID reader that interrogates RFID tags to gather data stored in the RFID tag. Other proximity detection strategies include logging Wi-Fi signals to gather a general area of where a device has been in range of different Wi-Fi routers.
However, existing solutions to proximity detection often require specialized hardware and/or only yield location ranges measured in city blocks. For example, RFID systems require specialty hardware for both the RFID reader and the RFID tag and Wi-Fi proximity strategies offer a very general detection location. Furthermore, detecting a device location using Wi-Fi may require a user to interact with the device (e.g. login to the Wi-Fi network) to log the Wi-Fi signals to gather data relevant to location.